Traffic Aware Inter-Layer Contact Selection for Multi-Layer Satellite Terrestrial Network

Satellite networks form part of the modern mobile network. In multi-layer satellite-terrestrial networks, Contact Graph Routing (CGR) enables to calculate an efficient delivery path which depends on the contact information configured in the contact plan. Due to the rapid relative motion between satellites which belong to different layers, the inter-layer contacts can suffer frequent disruption. In order to keep the integrity of the network, the inter-layer contact must be carefully selected to maintain connectivity yet avoid congestion. In this paper, we propose a traffic aware inter-layer contact selection method (TACS) by considering the flow situation of the associated nodes which contains the queue size, flow size, the number of connected nodes and the contact duration. We verify the performance of the proposed design in our Identifier/Locator (ID/Loc) split based satellite- terrestrial network testbed with 95 simulation nodes. Experiments show that the proposed design is able to achieve balanced flow distribution among MEO layer, improve the delivery ratio and reduce the delivery delay.